Joint for articulated arms



Nov. 5, 1940. P. Nf cLoU'nER I 2,220,216

JOINT FOR ARTICULATED ARMS Filed June 8, 1959 Patented Nov. 5, 1940 PATENT oFFlcE l JOINT FOR ARTICULATED ARMS Paul N. Cloutier, Decatur, Ill., assignor to Faries Manufacturing poration of Illinois Company, Decatur, Ill., a cor- Application June 8, 1939, Serial No. 278,002 Z Claims. (Cl. 28596.7)

My invention relates to that class of joints employed preferably in articulated arms used for dental brackets, although it 'will be clearly apparent from the hereinafter contained description that it is useful in many other locations.

VDevices of this class with which I am familiar, are subject to a very serious objection, in that no provision is made to take up the wear resulting from the constant rubbing against'each other of the two parts of the joint while in use. This friction results shortly in producing considerable looseness or play in the assembled fitting, which prevents the maintenance of the arm joint in a well tted and smooth acting condition.

My invention has for its principal object to provide a construction which will entirely and permanently overcome this diliculty byproviding a simple means of adjusting the joint to take up the wear. y

A further object of my invention is to provide a construction in which the ends of the arm sections will abut the inner rotary cylindrical sleeves thus providing means to rotate these sleeves.

A further object of my invention is to provide a construction which will insure a maximum of space for the electric wire .conductors -which are usually mounted in these joints when the articulated arms are used as a dental bracket and to avoid any sharp edges which might chafe the insulation on the wires making possible a short.

A further object is to provide a detent or stop which will prevent the sections being rotated a full circle or so that the wires cannot bev twisted off in this manner.

My means of accomplishing the foregoing ob-A jects may be more fully comprehended by having reference to the accompanying drawing, which is hereunto annexed and is a part of this specification in which:

Fig. 1 is a side elevational view of my device with parts broken away and shown in section for clarity;

Fig. 2 is an exploded View in elevation of my device, certain parts being shown in full elevation and other parts being shown in section; i

Fig. 3 is a. cross sectional view showing the electric wire outlet taken on line 3 3 of Fig. 1 and looking in the direction of the arrows; and

Fig, 4 is a cross sectional viewshowing the detent and stop taken on line 4 4 of Fig. l and looking in the direction of the arrows. Similar reference numerals refer to similar parts throughout the entire specification.

As shown in the drawing, the articulated arm,

cup-shaped member 5 has a threaded opening II 9 in its side in which is screwed the end 3 of the section I. After this is donel the parts are preferably soldered together. The cup-shaped member 5 has a shoulder I0 formed on its inner wall adjacent the open end l thereof, the object 151'" of which will be hereinafterexplained.

A rotary sleeve II which is provided with internal threads I2 is mounted inside the cupshaped member 5. This sleeve II is `provided with a .circumferential shoulder I3 adjacent its end I4. This end I4 extends into the other cupshaped member 6 and is provided with a detent or stop I5 which abuts the shoulder 30 formed onl the inner wall of the cup-shaped member 6. This detent I5 engages a pin or stop I6 mounted 25 on the shoulder I0 and this prevents the arm sections turning through 180 and in that manner twisting off the wire conductors.

The cup-shaped member 6 and the sleeve I I are held together by means of an annular member- `30' Il which is slidably and rotatably mounted on the sleeve II and abuts the circumferential shoulder I3. External threads I8 are cut or formed on the annular member I1 which are tted to internal' threads I9 shaped member 6. After member II has been v screwed into position, it holds the sleeve II* securely against axial movement though leaving the members free to rotate with relation to each other. able to solder this annular member I1 in place, thus insuring the joint against coming apart.

A cap screw 20 is placed in a central opening 2l formed in the closed end of the cup-shaped member 5 and is then screwed into the internal threads I2 in the rotary sleeve I I drawing the parts into a snug and secure joint.

In this position, the proper adjustment of the parts having been made, the end of the detent I5 will abut the shoulder I0 and slide upon it, as the 50 parts are rotated, until it contacts the pin or stop I6 on the shoulder and further rotation of the sections in that direction is impossible. A segment is milled 01T of the sleeve II forming a slot 22 through which the electric wires pass. 55

cut on the inner wall of thecup- I have found in practice that it is desir- 40 The outer face of both sides of the slot 22 are milled at, and these fiat walls 23 and 24 are located at each side of the opening 9 in the wall of the cup-shaped member 5 and are abutted by the end 3 of the section I, thus providing means to rotate the sleeve Il within the cupshaped members.

End 4 of section 2 is screwed into threaded opening 25 in the side of cup-shaped member 6 and isasmuch as the cup-shaped member 26 on the opposite end of section 2 is identical to the one described, except that it has a threaded opening 21 at its bottom to receive the vertical standard, a detailed description of the joint at this end of the arm 2 is deemed to be unnecessary.

When the parts become worn, all that is required to compensate for such wear is to tighten the cap screw 20 and the parts will be again drawn snugly together. It will be apparent to those skilled in the art that this can be done without the necessity of disassembling the joint. It will also be clear that by milling off the segment on the sleeve I l that I form ample room for the wires to be drawn through without endangering the insulation at all.

Having described my invention, what I regard as new and desire to secure by Letters Patent is:

l. A joint for an articulated arm comprising a pair of cup shaped members, one of said members having internal threads adjacent its open end, an externally threaded annular member mounted in said threads, a rotatable sleeve fitted in said annular member, a shoulder at one end of said sleeve adapted to abut said annular member, the upper cup shaped member having an internal groove adjacent one end adapted to enclose said annular member but spaced therefrom, means mounted in the upper cup shaped member to engage said sleeve to prevent axial movement of the two cup shaped members.

2. A pair of cup shaped members, a shouldered sleeve, means detachably mounted in one of said members which engage said shoulder, detachable means mounted in one end of the upper cup shaped member adapted to engage said sleeve whereby the wear caused by the friction of said members engaging each other can be taken up.

3. A pair of cup shaped members, an annular member detachably mounted in the lower cup shaped member adjacent its open end, a sleeve in the upper cup shaped member, the lower end of which extends through said annular member partially into the lower cup shaped member, an external shoulder on said sleeve which abuts the cup of said annular member, the upper cup shaped member having means mounted in its head which engages said sleeve and holds said cup shaped members against longitudinal movement but permits the two members to rotate with relation to each other.

4. A pair of cup shaped members, rotatable means mounted therein whereby said members are free to rotate with relation to each other, means detachably mounted in the head of the upper cup shaped member which engages said rotatable means and holds said cup shaped members against axial movement.

`5. A joint for an 4articulated arm, comprising a cup-shaped member, having a central opening in its closed end and a threaded side opening, an annular shoulder on its inner wall adjacent its open end, an internally threaded sleeve rotatably mounted in said cup-shaped member, a circumferential shoulder on said sleeve, a detent projecting axially from said shoulder, a screw fitted to the central opening in said sleeve which engages said threads, whereby the wear may be taken up, a segment of said sleeve being milled away, the flattened wall abutting the end of said section when the cup-shaped member is screwed on it, a second cup-shaped member having internal threads and a threaded opening in one side, an annular shoulder on its inner wall, a pin on said shoulder adapted to engage said detent, an annular member screwed into the threads n said second cup-shaped member, said sleeve being slidably and rotatably mounted therein, external threads on said annular member which fit the threads in the second cup-shaped member, and means to hold said annular member xedly in place.

6. A pair of cup shaped members, means del tachably secured in the lower cup shaped member, said means extending into the upper cup shaped member but being spaced therefrom, a sleeve provided with a shoulder at one end adapted to engage said detachable means, detachable means mounted in the head of the upper cup shaped member which engages said sleeve.

7 A joint for an articulated arm, comprising a cup-shaped member, having a central opening in its closed end and a threaded side opening, an annular shoulder on its inner wall adjacent its open end, an internally threaded sleeve rotatably mounted in said cup-shaped member, a circumferential shoulder on said sleeve, means to prevent the rotation of said members means to take up the wear of said cup-shaped members, means to hold said sleeve stationary, a second cup-shaped member having internal threads and a threaded opening in one side, an annular shoulder on its inner wall, an annular member screwed into the threads in said second cup-shaped member, said sleeve being slidably and rotatably mounted therein, external threads on saidy annular member which fit the threads in the second cup-shaped member, and means to hold said annular member xedly in place.

PAUL N. CLOUTIER. 

